LXR qemu/include/hw/timer/mc146818rtc

   1/*
   2 * QEMU MC146818 RTC emulation
   3 *
   4 * Copyright (c) 2003-2004 Fabrice Bellard
   5 *
   6 * Permission is hereby granted, free of charge, to any person obtaining a copy
   7 * of this software and associated documentation files (the "Software"), to deal
   8 * in the Software without restriction, including without limitation the rights
   9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10 * copies of the Software, and to permit persons to whom the Software is
  11 * furnished to do so, subject to the following conditions:
  12 *
  13 * The above copyright notice and this permission notice shall be included in
  14 * all copies or substantial portions of the Software.
  15 *
  16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22 * THE SOFTWARE.
  23 */
  24
  25#ifndef MC146818RTC_REGS_H
  26#define MC146818RTC_REGS_H
  27
  28#define RTC_ISA_IRQ 8
  29
  30#define RTC_SECONDS             0
  31#define RTC_SECONDS_ALARM       1
  32#define RTC_MINUTES             2
  33#define RTC_MINUTES_ALARM       3
  34#define RTC_HOURS               4
  35#define RTC_HOURS_ALARM         5
  36#define RTC_ALARM_DONT_CARE    0xC0
  37
  38#define RTC_DAY_OF_WEEK         6
  39#define RTC_DAY_OF_MONTH        7
  40#define RTC_MONTH               8
  41#define RTC_YEAR                9
  42
  43#define RTC_REG_A               10
  44#define RTC_REG_B               11
  45#define RTC_REG_C               12
  46#define RTC_REG_D               13
  47
  48/* PC cmos mappings */
  49#define RTC_CENTURY              0x32
  50#define RTC_IBM_PS2_CENTURY_BYTE 0x37
  51
  52#define REG_A_UIP 0x80
  53
  54#define REG_B_SET  0x80
  55#define REG_B_PIE  0x40
  56#define REG_B_AIE  0x20
  57#define REG_B_UIE  0x10
  58#define REG_B_SQWE 0x08
  59#define REG_B_DM   0x04
  60#define REG_B_24H  0x02
  61
  62#define REG_C_UF   0x10
  63#define REG_C_IRQF 0x80
  64#define REG_C_PF   0x40
  65#define REG_C_AF   0x20
  66#define REG_C_MASK 0x70
  67
  68static inline uint32_t periodic_period_to_clock(int period_code)
  69{
  70    if (!period_code) {
  71        return 0;
  72   }
  73
  74    if (period_code <= 2) {
  75        period_code += 7;
  76    }
  77    /* period in 32 Khz cycles */
  78   return 1 << (period_code - 1);
  79}
  80
  81#define RTC_CLOCK_RATE            32768
  82
  83static inline int64_t periodic_clock_to_ns(int64_t clocks)
  84{
  85    return muldiv64(clocks, NANOSECONDS_PER_SECOND, RTC_CLOCK_RATE);
  86}
  87
  88#endif
  89